Tar-Ciryatan was the twelfth King of Númenor. He succeeded his father, Tar-Minastir and it was said that he might have persuaded him to do so against his will.

With a great fleet of royal ships he traveled to Middle-earth, bringing numerous treasures back to Númenor. Though a powerful king, Tar-Ciryatan oppressed the men of Middle-earth and scorned his father's yearnings for an alliance with the Eldar. Those were considered the first signs of the Shadow's passing over Númenor.